System for recording use of structures deployed in association with heart tissue

ABSTRACT

A system records use of a structure deployed in operative association with heart tissue in a patient. An image controller generates an image of the structure while in use in the patient. An input receives data including information identifying the patient. An output processes the image in association with the data as a patient-specific, data base record for storage, retrieval, or manipulation.

FIELD OF THE INVENTION

[0001] The invention generally relates to systems and methods forguiding or locating diagnostic or therapeutic elements in interiorregions of the body.

BACKGROUND OF THE INVENTION

[0002] Physicians make use of catheters today in medical procedures togain access into interior regions of the body for diagnostic andtherapeutic purposes. It is important for the physician to be able toreliably and precisely position in proximity to desired tissuelocations. For example, the need for precise control over the catheteris especially critical during procedures that ablate myocardial tissuefrom within the heart. These procedures, called ablation therapy, areused to treat cardiac rhythm disturbances.

SUMMARY OF THE INVENTION

[0003] One aspect of the invention provides a system to record use of astructure deployed in operative association with heart tissue in apatient. An image controller generates an image of the structure whilein use in the patient. An input receives data including informationidentifying the patient. An output processes the image in associationwith the data as a patient-specific, data base record for storage,retrieval, or manipulation.

[0004] In a preferred embodiment, the data that forms part of the database record include other relevant information. For example, the dataincludes information identifying the procedure, or diagnosticinformation, or therapeutic information, or time stamped information, orprocessing information documenting the storage, retrieval, ormanipulation of the data, or information identifying a person other thanthe patient (such as the attending physician). In a preferredembodiment, the output password-protects the data base record.

[0005] In a preferred embodiment, the image controller includesfunctions to alter orientation, or shape, or view aspects of the imagebefore or after processing by the output. In a preferred embodiment, theimage controller also includes functions to mark or otherwise annotateone or more regions of the image in response to operator input before orafter processing by the output.

[0006] In a preferred embodiment, the image controller generates aproximity-indicating output showing the proximity of a roving element,deployed in the patient, to the structure.

[0007] Another aspect of the invention provides a system for diagnosingor treating cardiac conditions of multiple patients. The system includesa network of local work stations, each one adapted to be coupled to anelectrode structure, which, in use, is deployed in operative associationwith heart tissue of a patient. Each local work station includes animage controller to generate an image of the structure at leastpartially while the operative element performs a procedure in aninterior body region. An input receives data including informationidentifying the patient, and an output processes the image inassociation with the data as a patient-specific, data base record forstorage, retrieval, or manipulation. The system further includes acentral terminal coupled to the output of each work station. The centralterminal receives the patient-specific data base records for all workstations for storage in a central patient data base.

[0008] Other features and advantages of the inventions are set forth inthe following Description and Drawings, as well as in the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]FIG. 1 is schematic view of a system for sensing the position ofan operative element within a three-dimensional basket structure, inwhich an electrode on the operative element transmits an electricalfield, which is sensed by one or more electrodes on the basketstructure;

[0010]FIG. 2A is a side view of the three-dimensional basket structurecarried by a catheter tube, which-forms a part of the system shown inFIG. 1;

[0011]FIG. 2B is a side view of the operative element carried by acatheter tube, which forms a part of the system shown in FIG. 1;

[0012]FIG. 3 is a schematic view of the processing element which forms apart of the system shown in FIG. 1;

[0013]FIG. 4 is a graph exemplifying how normalized voltage sensed by anelectrode carried by the three-dimensional basket structure changes inrelation to the proximity of the electrode to the operative element,which is a relationship that the system shown in FIG. 1 uses to generatea proximity-indicating output;

[0014]FIG. 5 is a hard-wired display device displaying a polar view of athree-dimensional basket structure, which visually displays the presenceor absence of a proximity-indicated output at each electrode carried bythe three-dimensional basket structure;

[0015]FIG. 6 is a schematic view of an embodiment of a graphical userinterface used by the system to visually display the presence or absenceof a proximity-indicated output at each electrode carried by thethree-dimensional basket structure;

[0016]FIG. 7 is a representative view of the split viewing screen of thegraphical user interface shown in FIG. 6, showing the idealized model ofthe three-dimensional basket structure generated by the interface atdifferent idealized orientations;

[0017]FIG. 8 is a schematic view an idealized model of athree-dimensional basket structure generated by the interface, showingthe interpolation of multiple proximity-indicated outputs;

[0018]FIG. 9 is a schematic view of the system shown in FIG. 1 as partof a modular system used to diagnose and treat cardiac conditions;

[0019]FIGS. 10A and 10B are representative views of the split viewingscreen of the graphical user interface shown in FIG. 9, showing the useof markers and comments in association with the idealized model of thethree-dimensional basket structure that the interface generates;

[0020]FIG. 11 is a representative view of the viewing screen of thegraphical user interface shown in FIG. 9, showing the pop up PatientData Menu used to establish and maintain a patient-specific data base;

[0021]FIG. 12 is a schematic view of a system for sensing the positionof an operative element with respect to an elongated electrode array;

[0022]FIG. 13 is a diagrammatic view of the operative element andelongated electrode array shown in FIG. 12 deployed for diagnostic ortherapeutic purposes in the annulus region of a human heart;

[0023]FIG. 14 is a schematic view of an embodiment of a Graphical userinterface used by the system shown in FIG. 12 to visually display thepresence or absence of a proximity-indicated out-put at each electrodecarried by the elongated electrode array;

[0024]FIG. 15 is a schematic view of a system for sensing the positionof an operative element with respect to a multiple electrode loopstructure;

[0025]FIG. 16 is a side view of an exemplary multiple electrode loopstructure suitable for use with the system shown in FIG. 15, with theloop structure withdrawn within an associated sheath for deployment intoa body region;

[0026]FIG. 17 is a perspective view of the multiple electrode loopstructure shown in FIG. 16, with the loop structure deployed for usebeyond the associated sheath;

[0027]FIG. 18 is a diagrammatic view of the operative element andmultiple electrode loop structure shown in FIG. 15 deployed fordiagnostic or therapeutic purposes in the annulus region of a humanheart;

[0028]FIG. 19 is a schematic view of an embodiment of a graphical userinterface used by the system shown in FIG. 15 to visually display thepresence or absence of a proximity-indicated out-put at each electrodecarried by the loop structure;

[0029]FIG. 20 is schematic view of a system for sensing the position ofan operative element within a three-dimensional basket structure, inwhich one or more electrodes on the basket structure transmit anelectrical field, which is sensed by an electrode on the operativeelement;

[0030]FIG. 21 is a schematic view of the processing element which formsa part of the system shown in FIG. 20;

[0031]FIG. 22 is schematic view of an operative element oriented with aspline of the basket structure, as shown in FIG. 20, in which theelectrical field is sensed by multiple electrodes on the operativeelement, which is shown in a not-parallel orientation with respect tothe spline;

[0032]FIG. 23 is schematic view of the operative element oriented withthe spline, like that shown in FIG. 22, except that the operativeelement is shown in more-parallel orientation with respect to thespline;

[0033]FIG. 24 is a schematic view an idealized model of the spline shownin FIG. 23 generated by the interface, showing the interpolation ofmultiple proximity-indicated outputs;

[0034]FIG. 25 is an end perspective view of a dual electrode arraystructure having both an inner array of sensing electrodes and an outerarray of sensing electrodes to locate a roving operative element bothnear a tissue wall and within the middle of an interior body regionspaced from the tissue wall;

[0035]FIG. 26 is an alternative embodiment of a dual electrode arraystructure having inner and outer arrays of sensing electrodes;

[0036]FIG. 27 is schematic view of a system for sensing the position ofan operative element within a dual electrode array structure of the typeshown in FIGS. 25 and 26;

[0037]FIG. 28 is a schematic view of an embodiment of a graphical userinterface used by the system shown in FIG. 27 to visually display thepresence or absence of a proximity-indicated out-put at each electrodecarried by the dual electrode array structure;

[0038]FIG. 29 is schematic view of a system for sensing the position ofan operative element within a three-dimensional basket structure, inwhich one electrode on the operative element transmits an electricalfield, which is sensed by an other electrode on the operative elementand by one or more electrodes on the basket structure; and

[0039]FIG. 30 is a schematic view of the processing element which formsa part of the system shown in FIG. 29.

[0040] The invention may be embodied in several forms without departingfrom its spirit or essential characteristics. The scope of the inventionis defined in the appended claims, rather than in the specificdescription preceding them. All embodiments that fall within the meaningand range of equivalency of the claims are therefore intended to beembraced by the claims.

DESCRIPTION OF THE PREFERRED EMBODIMENTS I. Proximity sensing WithinThree-Dimensional Structures

[0041]FIG. 1 shows one embodiment of a position sensing system 10, whichlocates the position of an operative element 12 within a space(designated S). The system 10 is well adapted for use inside bodylumens, chambers or cavities for either diagnostic or therapeuticpurposes. For this reason, the system 10 will be described in thecontext of its use within a living body. The system 10 particularlylends itself to catheter-based procedures, where access to the interiorbody region is obtained, for example, through the vascular system oralimentary canal, without complex, invasive surgical procedures.

[0042] For example, the system 10 can be used during the diagnosis andtreatment of arrhythmia conditions within the heart, such as ventriculartachycardia or atrial fibrillation. The system 10 also can be usedduring the diagnosis or treatment of intravascular ailments, inassociation, for example, with angioplasty or atherectomy techniques.The system 10 also can be used during the diagnosis or treatment ofailments in the gastrointestinal tract, the prostrate, brain, gallbladder, uterus, and other regions of the body.

[0043] A. The Operative Element

[0044] For deployment into an interior body space S, the operativeelement 12 is carried at the distal end of a catheter tube 44 (as FIG.2B also shows). Nevertheless, the system 10 an also be used inassociation with systems and methods that are not necessarilycatheter-based, e.g., laser delivery devices, atherectomy devices,transmyocardial revascularization (TMR), or percutaneous myocardialrevascularization (PMR).

[0045] The operative element 12 an take different forms and can be usedfor either therapeutic purposes, or diagnostic purposes, or both. Theoperative element 12 an comprise, for example, a device for imaging bodytissue, such as an ultrasound transducer or an array of ultrasoundtransducers, or an optic fiber element. Alternatively, the operativeelement 12 an comprise a device to deliver a drug or therapeuticmaterial to body tissue. Still alternatively, the operative element 12an comprise a device, e.g., an electrode, for sensing a physiologicalcharacteristic in tissue, such as electrical activity in heart tissue,or for transmitting energy to stimulate or ablate tissue.

[0046] B. Three-Dimensional Locating Probe

[0047] The system 10 includes a locating probe 14 (see FIG. 2A also),which, like the operative element 12 is carried at the distal end of acatheter tube 45 for introduction into the body space S. In theembodiment illustrated in FIG. 1, the locating probe 14 comprises acomposite, three-dimensional basket structure. As will be describedlater, the structure of the locating probe 14 can take other forms.

[0048] As best shown in FIG. 2A, the structure 14 includes eight spacedapart spline elements 20 assembled together by a distal hub 16 and aproximal base 18. Each spline 20, in turn, carries eight electrodes 22,for a total of sixty-four 44 electrodes 22 positioned about the space S.Of course, a greater or lesser number of spline elements 20 and/orelectrodes 22 can be present.

[0049] Each spline element 20 preferably comprises a flexible body madefrom resilient, inert wire or plastic. Elastic memory material such asnickel titanium (commercially available as NITINOL™ material) can beused. Resilient injection molded plastic or stainless steel can also beused. Each spline element 20 is preferably preformed with a convex bias,creating a normally open three-dimensional basket structure.

[0050] As FIG. 2A shows, an outer sheath 24 can be advanced by slidingforward along the catheter tube 45 to compress and collapses thestructure 14 for introduction into the body region. Rearward movementretracts the slidable sheath 24 away from the structure 14, whichsprings open and assumes its three-dimensional shape.

[0051] In FIGS. 1 and 2A, the geometry of spline elements 20 is shown tobe both radially and axially symmetric. Asymmetric structures, eitherradially or axially or both, can also be used. Examples of asymmetricarrays of spline structures are shown in copending U.S. application Ser.No. 08/742,569, filed Oct. 28, 1996 and entitled “Asymmetric MultipleElectrode Support Structures,” which is incorporated herein byreference.

[0052]FIG. 1 identifies the electrodes 22 by the set designation (A,B),where A=1 to p and B=1 to e, where p is the total number of splines 20and e is the number of electrodes 22 on each spline 20 (in theillustrated embodiment, p=8 and e=8).

[0053] It should be appreciated that the locating probe 14 need not be acomposite basket structure, but instead exist as separate probes locatedabout the space S. However, the composite basket structure 14 is wellsuited for use within the heart and can perform other functions inaddition to navigation, such as pacing and mapping, as will be describedin greater detail later.

[0054] C. Generation of Proximity-Indicating Output

[0055] (i) Transmission of Electrical

[0056] Field by Roving Electrode

[0057] As FIG. 1 shows, a central processing unit 28 conditions anoscillator 26 to generate an electrical alternating current (AC)waveform at a predetermined amplitude and frequency. The centralprocessing unit 28 couples the oscillator 26 to a transmitting electrode30 carried by the roving operative element 12 The electrode 30 may be acomponent added to the operative element 12 or it may comprise acomponent already on the operative element 12 but used for an additionalpurpose.

[0058] An indifferent electrode 32, carried as a patch on the exteriorof the patient, comprises the voltage return, which is, in turn, coupledto an electrical reference. In the illustrated embodiment, theelectrical reference is isolated or patient ground 34, although otherreferences can be used. Alternatively, another electrode carried by theoperative element 12 an serve as the voltage return. As anotheralternative, an electrode (A,B) on the structure 14 can also serve asthe voltage return. A voltage field is established, which varies indetected amplitude at each basket electrode (A,B) according to itsdistance from the electrode 30 carried by the operative element 12 Foruse within a living body space, the selected current amplitude of theoscillator output can vary between 0.1 mAmp to about 5 mAmp. Thefrequency selected can also vary from about 5 kHz to about 100 kHz.Currents substantially above about 5 mAmp and frequencies substantiallybelow 5 KHz should be avoided when heart tissue is nearby, as they posethe danger of inducing fibrillation. The maximum current that can beused while avoiding fibrillation is a function of the frequency, asexpressed in the following equation:

I=ƒ×10

[0059] where I is current in μAmp, and f is frequency in kHz.

[0060] The shape of the waveform can also vary. In the illustrated andpreferred embodiment, the waveform is sinusoidal. However, square waveshapes or pulses can also be used, although harmonics may be encounteredif capacitive coupling is present. Furthermore, the waveform need not becontinuous. The oscillator 26 may generate pulsed waveforms.

[0061] The system 10 includes a data acquisition element 36 coupled tothe central processing unit 28 and to a switch or suitable multiplexerelement 38. The switch element 38individually conditions each electrode(A,B) on the structure 14 to sense a local voltage amplitude V_(S(A,B)).The data acquisition element 36 includes an amplitude detector 37 (seeFIG. 3), which acquires V_(S(A,B)) for each electrode 22 in associationwith the electrode's (A,B) position coordinates.

[0062] The switch element 38 also conditions the electrode 30 on theoperative element 12 o sense a local voltage amplitude V_(O(A,B)) at thesame time V_(S(A,B)) is sensed by each basket electrode (A,B). The dataacquisition element 36 includes a second amplitude detector 39 (see FIG.3), which acquires a V_(O(A,B)) in association with each V_(S(A,B)).

[0063] As FIG. 1 further shows, the central processing unit 28 includesa processing element 40. The processing element 40 includes a component42 (see FIG. 3), which derives a normalized detected voltage valueV_(N(A,B)) for each acquired V_(O(A,B)) and V_(S(A,B)) data set, asfollows: $V_{N{({A,B})}} = \frac{V_{S{({A,B})}}}{V_{O{({A,B})}}}$

[0064] As FIG. 3 also shows, the processing element 40 further includesa comparator 46. The comparator 46 receives as input 43 the normalizeddetected voltage value VN(A,B) generated by the component 42. Thecomparator 46 also receives as input 41 a set line voltage, whichconstitutes a predetermined nominal voltage threshold value V_(THRESH).The comparator 46 compares the magnitude of V_(N(A,B)) (input line 43)to the magnitude of V_(THRESH) (input line 41).

[0065] The predetermined nominal voltage threshold value V_(THRESH)establishes a nominal separation distance between the electrode 30 onthe operative element 12 nd a given basket electrode (A,B). Thethreshold voltage value V_(THRESH) serves to differentiate between a“close condition” between the electrode 30 on the operative element 12nd a given basket electrode (A,B)(i.e., equal to or less than thenominal distance) and a “far condition” between the electrode 30 on theoperative element 12 and a given basket electrode (A,B)(i.e., greaterthan the nominal distance).

[0066] If V_(N(A,B)) is greater than or equal to V_(THRESH), thecomparator 46 generates a proximity-indicating output 47, also designedP_((A,B)), for the basket electrode (A,B). The proximity-indicatedoutput P_((A,B)) for a given electrode (A,B) notifies the physician thatthe requisite “close condition” exists between the electrode 30 on theoperative element 12 and the particular basket electrode (A,B).

[0067] When V_(N(A<B)) is less than V_(TNRESH) , the comparator 46generates no output for the particular electrode (A,B). The absence of aproximity-indicating output P_((A,B)) for a particular electrode (A,B)notifies the physician that the requisite “far condition” exists betweenthe electrode 30 on the operative element 12 nd the particular basketelectrode (A,B).

[0068] The magnitude selected for the threshold value V_(THRESH) setsthe spacial criteria for “close condition” and “far condition,” giventhe physical characteristics of the electrode 30 on the operativeelement 12 nd the physical characteristics of the electrode (A,B) on thestructure 14. The physical characteristics include the diameter andshape of the electrode, as well as the electrical conductivity of thematerial from which the electrode is made and the electrical propertiesof the conductive medium exiting between the electrode 30 and thestructure 14 (for example, a blood pool or myocardial tissue mass)

[0069] The relationship between distance and expected normalized voltagedetected value V_(N(A,B)) for a given electrode 30 on the operativeelement 12 nd a given electrode (A,B) on the structure 14 can bedetermined empirically, e.g., by in vitro or in vivo testing or byfinite element analysis. FIG. 4 shows a representative data plot,showing the relationship between expected normalized voltage detectedvalues V_(N(A,B)) for a given electrode type on the operative element 12nd a given electrode type on the structure 14. The plot in FIG. 4 showsthat V_(N(A,B)) (which is not expressed in units of volts, as itrepresents a normalized value derived by dividing two voltages)increases as the distance (in mm) between the electrode 30 and a basketelectrode (A,B) decreases. For example, in FIG. 4, at a distance of 4mm, the expected normalized voltage detected value V_(N(A,B)) is about0.5 units, whereas, at a distance of about 1 mm, the expected normalizedvoltage detected value V_(N(A,B)) is about 0.8 units.

[0070] By selecting an expected normalized voltage detected valueV_(N(A,B)) as the threshold V_(THRESH), the operator is able to definethe nominal distance between a given electrode 30 on the operativeelement 12 nd a given electrode (A,B) on the structure 14 at which theproximity-indicating output P_((A,B)) is first generated.

[0071] The threshold value V_(THRESH) is the voltage line input 46 tothe comparator 46. The value of V_(THRESH) can be set at a desired fixedvoltage value representing a nominal threshold distance. In theillustrated and preferred embodiment, the processing element 40 includesan input 50 by which the physician can designate a value for the nominaldistance. For example, the physician can designate the nominal distancewithin a range of distances of 1 mm to 5 mm. The processing element 40includes a look-up table 52 or its equivalent, which expresses theempirically determined relationship between voltage and distance (whichFIG. 4 exemplifies). Using the table, the processing element 40 convertsthe distance value entered by input 50 to a corresponding normalizedvoltage value, which constitutes V_(THRESH). The processing element 40also includes a voltage regulator 54, which sets the voltage line input46 to the normalized voltage value (V_(THRESH)), to thereby achieve thespacial sensitivity established by the physician for theproximity-indicating output P_((A,B)).

[0072] The operative components controlled by the central processingunit 28, as previously discussed, can incorporate the particularelectrical configuration shown in FIGS. 1 and 3, or another analog ordigital configuration, to carry out the signal sampling and processingfunctions as described.

[0073] (ii) Transmission of Electrical Field by One or More StationaryElectrodes

[0074] As FIG. 20 shows, the central processing unit 28 can couple theoscillator 26 (through the switch or suitable multiplexer element 38) toone or more electrodes 22 carried by the structure 14. The indifferentelectrode 32 remains the voltage return, being coupled to an electricalreference, which, in the illustrated embodiment, is isolated or patientground 34. As before stated, alternatively, another electrode carried bythe operative element 12 an serve as the voltage return, or an electrode22 on the structure 14 can also serve as the voltage return.

[0075] The transmission of electrical energy from one or more of theelectrodes 22 on the structure 14 to the indifferent electrode 32establishes a voltage field, like that earlier described in connectionwith FIGS. 1 and 3. The voltage field will vary in detected amplitude atthe roving electrode 30 according to its distance from the transmittingbasket electrode (A,B).

[0076] In this configuration (see FIG. 21, as well) the switch element38 individually conditions a selected one or group of electrodes (A,B)on the structure 14 to transmit electrical energy. The switch element 38also conditions each selected transmitting electrode (A,B) on thestructure 14 to sense a local voltage amplitude V_(S(A,B)). The dataacquisition element 36 includes the amplitude detector 37 (see FIG. 21),which acquires V_(S(A,B)) for each transmitting electrode 22 inassociation with the electrode's (A,B) position coordinates.

[0077] The switch element 36 also conditions the electrode 30 on theoperative element 12 to sense a local voltage amplitude V_(O(A,B)) atthe same time V_(S(A,B)) is sensed by each transmitting basket electrode(A,B). The data acquisition element 36 includes the second amplitudedetector 39 (see FIG. 21), which acquires a V_(O(A,B)) in associationwith each V_(S(A,B)).

[0078] The component 42 of the processing element 40 (see FIG. 21)derives a normalized detected voltage value V_(N(A,B)) for each acquiredV_(O(A,B)) and V_(S(A,B)) data set, as follows:$V_{N{({A,B})}} = \frac{V_{O{({A,B})}}}{V_{S{({A,B})}}}$

[0079] Although the positions of the numerator and denominatorquantities are reversed for V_(N(A,B)) in the embodiment shown in FIGS.20 and 21, compared to the embodiment shown in FIGS. 1 and 3, thenormalized detected voltage value V_(N(A,B)) is derived in the sameconceptual way. More universally expressed, the normalized detectedvoltage value V_(N(A,B)) is derived by dividing the local voltageamplitude sensed by the transmitting electrode V_(TRANS) into the localvoltage amplitude sensed by the other non-transmitting, sense-onlyelectrode V_(SENSE), or: $V_{N} = \frac{V_{SENSE}}{V_{TRANS}}$

[0080] As FIG. 21 shows, the processing element 40 includes thecomparator 46. The comparator 46 receives as input 43 the normalizeddetected voltage value V_(N(A,B)) generated by the component 42. Thecomparator 46 also receives as input 41 a set line voltage, whichconstitutes the predetermined nominal voltage threshold valueV_(THRESH), as previously described. The comparator 46 compares themagnitude of V_(N(A,B)) (input line 43) to the magnitude of V_(THRESH)(input line 41). Also as previously described, if V_(N(A,B)) is greaterthan or equal to V_(THRESH), the comparator 46 generates aproximity-indicating output 47 (also designed P_((A,B))) for the basketelectrode (A,B). Conversely, when V_(N(A<B)) is less than V_(THRESH) thecomparator 46 generates no output for the particular electrode (A,B).

[0081] As FIG. 22 shows, the roving element 12 an carry several sensingelectrodes (three are shown for purposes of illustration, designated30(1), 30(2), and 30(1)). The use of several sensing electrodes 30(1),30(2), and 30(3) in the embodiment shown in FIGS. 20 and 22 allows thephysician to assess, not only proximity information, but alsoinformation pertaining to the orientation of the roving element 12itself.

[0082] More particularly, the switch element 38 individually conditionsall electrodes (A,B) along an entire spline 20 of the structure 14 totransmit electrical energy and to sense a local voltage amplitudeV_(S(A,B)) at each transmitting electrode (A,B) along the spline 20. Theswitch element 38 also conditions each electrode 30(1), 30(2), and 30(3)on the operative element 12 o sense a local voltage amplitude V_(O(A,B))at the same time V_(S(A,B)) is sensed by each transmitting basketelectrode (A,B). The normalized detected voltage value V_(N(A,B)) isgenerated for each combination of transmitting basket electrode (A,B)and non-transmitting, sense-only electrode 30(1), 30(2), and 30(3) andcompared the magnitude of the threshold voltage V_(THRESH) (input line41).

[0083] The resulting generation of one or more proximity-indicationoutputs provides orientation information. For example, in FIG. 22, theaxis of the roving element 12 is oriented in a not-parallel relationshipwith axis of the spline 20. The roving electrode 30(1) lays in a closecondition to only two of the spline electrodes 22(2) and 22(3). Theresulting two proximity-indicating outputs P(22(2)) and P(22(3)) for theelectrode 30(1), and the absence of proximity-indicating outputs for theother roving electrodes 30(2) and 30(3), denotes that the axis of theroving element 12 s oriented generally not-parallel or “head-on” withrespect to the axis of the spline 20.

[0084] In FIG. 23, the axis of the roving element 12 is oriented in amore-parallel relationship with the spline 20. In this orientation, theroving electrode 30(1) lays in a close condition to the spline electrode22(4); the roving electrode 30(2) lays in a close condition to twospline electrodes 22(3) and 22(4); and the roving electrode 30(3) laysin a close condition to two spline electrodes 22(2) and 22(3). Multipleproximity-indicating outputs result: one output P(22(4)) for rovingelectrode 30(1); two outputs P(22(4)) and P(22(3)) for roving electrode30(2); and two outputs P(22(2)) and P(22(3)) for roving electrode 30(3).The pattern of proximity-indicating outputs for all roving electrodes30(1), 30(2), and 30(3) denotes that the roving element 12 s orientedgenerally parallel or “side-by-side” with respect to the axis of thespline 20.

[0085] Transmitting an electrical field from all electrodes along aspline, sequentially about each spline of a three-dimensional basketstructure 14, generates a pattern of proximity-indicating outputs. Thepattern locates the position and orientation of the operative element 12within the three-dimensional space the basket structure 14 defines.

[0086] More particularly, as FIGS. 22 and 23 demonstrate, for a givenelectrode 30(1), 30(2), or 30(3) selected on the roving element 12 thenumber proximity-indicating outputs varies according to proximity of theselected electrode to one or more the electrodes 22(1), 22(2), 22(3),and 22(4) on the spline 20. The number of proximity-indicating outputsfor a given electrode 30(1), or 30(2), or 30(3) will increase inproportion to the number of basket electrodes 22(1) to 22(4) inproximity to it. As FIGS. 22 and 23 also demonstrate, the total numberof position-indicating outputs combined for all the electrodes 30(1) to30(3) varies according to the orientation of the axis of the rovingelectrode to the axis of the spline 20. As the axis of the rovingelectrode 12 becomes more parallel to the axis of the spline 20, thetotal number of proximity-indicated outputs for all the electrodes 30(1)to 30(3) will increase.

[0087] As will be described in greater detail later, the pattern ofmultiple, simultaneous proximity-indicating outputs can be interpolatedfor display purposes.

[0088] (iii) Transmission of Electrical Field by An Other RovingElectrode

[0089] As FIG. 29 shows, the roving operative element 12 an carry, inaddition to a single sensing electrode 30 or multiple sensing electrodes30(1), 30(2), and 30(3), an energy transmitting electrode 260. In theillustrated embodiment, the electrode 260 comprises a ring ofelectrically conductive material, spaced proximally of the single ormultiple sensing electrodes 30. Of course, the electrode 260 can takeother forms, as will be discussed later in connection with otherelectrode structures.

[0090] In this embodiment, the central processing unit 28 couples theoscillator 26 to the roving electrode 260. The indifferent electrode 32remains the voltage return, being coupled to an electrical reference,which, in the illustrated embodiment, is isolated or patient ground 34.As before stated, alternatively, another electrode carried by theoperative element 12 an serve as the voltage return, or an electrode 22on the structure 14 can also serve as the voltage return.

[0091] The transmission of electrical energy from the electrode 260 tothe indifferent electrode 32 establishes a voltage field, like thatearlier described in connection with FIGS. 1 and 3, and FIGS. 20 and 21.The voltage field will vary in detected amplitude at the rovingelectrode 30 according to its distance from a given electrode (A,B) onthe structure 14.

[0092] In this embodiment, neither the roving electrode 30 nor any ofthe electrodes (A,B) on the structure 14 transmits the electrical field.Instead (see FIG. 30 ) the switch element 38 individually conditions aselected one or group of electrodes (A,B) on the structure 14 to sense alocal voltage amplitude V_(S(A,B)). The data acquisition element 36includes the amplitude detector 37 (see FIG. 30 ), which acquiresV_(S(A,B)) for each electrode 22 in association with the electrode's(A,B) position coordinates.

[0093] The switch element 36 also conditions the sensing electrode orelectrodes 30 on the operative element 12 o sense a local voltageamplitude V_(O(A,B)) at the same time V_(S(A,B)) is sensed by eachtransmitting basket electrode (A,B). The data acquisition element 36includes the second amplitude detector 39 (see FIG. 30 ), which acquiresa V_(O(A,B)) in association with each V_(S(A,B)).

[0094] The component 42 of the processing element 40 (see FIG. 30 )derives a normalized detected voltage value V_(N(A,B)) for each acquiredV_(O(A,B)) and V_(S(A,B)) data set, as follows:$V_{N{({A,B})}} = \frac{V_{S{({A,B})}}}{V_{O{({A,B})}}}$

[0095] As FIG. 30 shows, the processing element 40 includes thecomparator 46. The comparator 46 receives as input 43 the normalizeddetected voltage value V_(N(A,B)) generated by the component 42. Thecomparator 46 also receives as input 41 a set line voltage, whichconstitutes the predetermined nominal voltage threshold valueV_(THRESH), as previously described. The comparator 46 compares themagnitude of V_(N(A,B)) (input line 43) to the magnitude of V_(THRESH)(input line 41). Also as previously described, if V_(N(A,B)) is greaterthan or equal to V_(THRESH), the comparator 46 generates aproximity-indicating output 47 (also designed P_((A,B))) for the basketelectrode (A,B). Conversely, when V_(N(A<B)) is less than V_(THRESH),the comparator 46 generates no output for the particular electrode(A,B).

[0096] D. Displaying the Proximity-Indicating Output

[0097] In the illustrated and preferred embodiment, the system 10includes an output display device 56 coupled to the processing element40. The device 56 presents the presence or absence ofproximity-indicating outputs P_((A,B)) for each basket electrode (A,B)in a visual or graphic format useful to the physician for remotelylocating and guiding the operative element 12 relative to the structure14.

[0098] (i) Hard-Wired Polar Grid

[0099] In one embodiment (see FIG. 5), the output display device 56comprises a hard-wired grid 58 of individual light emitting diodes 60(LED's) arranged to depict a polar map of all the electrodes (A,B)carried by the basket structure 14. The LED's 60 are normally maintainedin an designated “OFF” state by the processing element 40. The LED's 60can be unlit in the “OFF” state.

[0100] When a proximity-indicating output P_((A,B)) is generated for agiven basket electrode (A,B), the processing element 40 switches to an“ON” state the LED 60 that marks the location of the given electrode(A,B) on the hard-wired grid 58. The LED 60, when switched “ON,”displays a color, e.g., green, to visually signal to the physician theproximity of the operative element 12 to the given basket electrode(A,B).

[0101] It is possible for more than one LED 60 on the hard-wired grid 58to be switched “ON” at the same time, depending upon the orientation ofthe operative element 12 to the basket electrodes (A,B) and the spacialsensitivity established for the comparator 46.

[0102] (ii) Graphical Display

[0103] In a preferred embodiment (see FIG. 6), the output display device56 comprises a Graphical User Interface (GUI) 62. The GUI 62 isimplemented by a graphical control program 82 resident in an externalmicroprocessor based computer control, such as a laptop computer 64having a keyboard 66, a display screen 68, and mouse 70. The laptopcomputer 64 is coupled to the processing element 40 (and thus also tothe central processing unit 28) via a communication port 72, such as RS232 or an Ethernet™ connection.

[0104] The processing element 40 (or alternatively, the centralprocessing unit 28) conditions the GUI graphical control program 82 togenerate on the display screen 68 an idealized graphical image 74, whichmodels the geometry of the particular basket structure 14 deployed inthe body region. By reference to this model image 74, the physician isable to visualize the location of each basket electrode (A,B) and spline20.

[0105] In the illustrated and preferred embodiment (see FIGS. 6 and 7),the GUI control program 82 provides a split screen image having a leftpanel 76 and a right panel 78. The image 74 of the basket structure 14appears in the left and right panels 76 and 78 as a modeled wire-frameimage, with electrodes (A,B) spatially arranged and appearing as nodes80.

[0106] The panels 76 and 78 make it possible to simultaneously displaythe image 74 from different idealized orientations. A control program 82generates an Operational Screen Toolbar 150 (see FIG. 7), which providesthe physician with a variety of options to customize the idealized image74 in each panel 76 or 78. For example (as FIG. 7 shows), the left panel76 can show the image 74 from a selected oblique angle, such as a rightor left anterior angle or a right or left posterior oblique angle, whilethe right panel 78 can show the image 74 from a selected orthogonal sideangle.

[0107] In the illustrated embodiment (see FIG. 7), the Toolbar 150includes an array of View buttons 156. The View Buttons 156 allow thephysician to choose among typical orientations for the image 74 in theleft panel 76, such as Left 45° or 30° (designated respectively LAO45LAO30 in FIG. 7), Right 45° or 30° (designated respectively RAO45 RAO30in FIG. 7), or Anterior/Posterior (designated A/P in FIG. 7). The image74 in the right panel 78 is consistent with the orientation selected forthe image in the left panel, however, another array of View buttons 158allows the physician to select among typical views for the right panelimage, such as Superior, Inferior, Left, and Right.

[0108] Thus, by pointing and clicking the mouse 70, or by making commandentries using the keyboard 66, the physician is able to set up thedesired views in the left and right panels 76 and 78. By clicking theSave View button 152 in the Toolbar 150, the physician is able to savethe image in an associated patient data base 12 (see FIG. 9), thedetails of which will be described later.

[0109] A fluoroscope or other imaging device may be used in associationwith the GUI 62 to visualize the actual orientation of the basketstructure 14 and operative element 12 n the body region. The GUI 62provides a simplified and idealized representation that supplements thefluoroscopic or other independent image.

[0110] In the illustrated embodiment, the physician can compare thefluoroscopic or other independent image and manipulate the GUI image 74to more closely match the view of the fluoroscopic display. Toaccomplish this (see FIG. 7), the Toolbar 150 includes a set ofon-screen X, Y, and Z buttons 92, which can be clicked to cause at leastone of the model images 74 to incrementally rotate about idealized X, Y,Z coordinate axes.

[0111] In a preferred embodiment, the control program 82 can becontrolled by the mouse 70 to change the shape of the idealized image 74to more closely match the shape of the structure 14 as seen in afluoroscopic or other independent view. The shape of the image 74 can beformed by dragging the mouse 70, for example, to appear in a range ofconfigurations from spherical to a more elongated ellipsoid (when thestructure is a three-dimensional basket structure, as shown in FIG. 1)or to appear in a range of curve radii for an elongated, curvilinearstructure (as will be described later). The shape characteristic formedby the physician is saved along with other image information when thesave button 152 is clicked.

[0112] When saving any image manipulated by use of the Toolbar 150,e.g., to match the particular fluoroscopic or other independent view,the control program 82 allows the physician to uniquely associate theview with one of the preset view buttons 156 or 158, or to create a newcustom view button with a custom name for the view. This allows thephysician to quickly recall and switch among any view image previouslysaved. Using the Toolbar 150, the physician can switch views of thegraphic image 74 electronically, without manipulating the fluoroscopicdisplay.

[0113] The GUI control program 82 initialized the nodes 80 on the modelimage 74 at a designated color or shade. The initialized color or shadefor a given node 80 constitutes a visual signal to the physician, thatthe operative element 12 s at a “far condition” relative to theassociated electrode (A,B).

[0114] A proximity-indicating output P_((A,B)) generated by theprocessing element 40 for a given electrode (A,B) is transmitted to thecontrol program 82. The control program 82 switches “ON” the node 80(*)marking the location of the given electrode (A,B) in the image 74, bychanging the designated color or shade. The node 80, when switched “ON,”displays a different color or shade, e.g., green, to visually signal thephysician that the operative element 12 s in a “Close Condition”relative to the corresponding basket electrode (A,B).

[0115] In the illustrated and preferred embodiment (see FIG. 7), thephysician is able to point and click the mouse 70 on a SensitivityAdjustment button 154 on the Toolbar 150 (or enter commands by thekeyboard 66) to open a pop-up Sensitivity Adjustment Window 84. TheWindow 84 allows the physician to access the input 50 at any pointduring the procedure, to alter the spacial sensitivity for theproximity-indicating output P_((A,B)).

[0116] In the illustrated embodiment, the Window 84 includes a slideicon 86, which can be dragged by the mouse 70 (or moved by acorresponding keyboard command) between a “Coarse” setting and a “Fine”setting. The “Coarse” setting selects a low-relative value for input 50,in response to which the central processing element 40 sets a V_(THRESH)corresponding to a large-relative nominal distance (for example, at 5mm). The “Fine” setting selects a high-relative value for input 50, inresponse to which the processing element 40 sets a V_(THRESH)corresponding to a small-relative nominal distance (for example, at 1mm). The Window 84 can also displays in alpha/numeric format the currentselected nominal distance. The physician is thereby able, in real timeduring the procedure, to adjust the sensitivity at which theproximity-indicating output P_((A,B)) is generated, to obtain thedesired resolution for the displayed model image 74.

[0117] It is possible for more than one node 80 to be switched “ON” atthe same time, depending upon the orientation of the operative element12 o the basket electrodes (A,B) and the spacial sensitivityestablished. In the illustrated and preferred embodiment (see FIG. 6),the graphical control program 82, includes an interpolating function 88.

[0118] As illustrated in FIG. 8, if two nodes 80 are ordered to beswitched “ON” simultaneously (for example, nodes 80(10) and 80(11) inFIG. 8), the interpolating function 88 switches “ON” a phantom node80(10,11) midway between the two electrode nodes 80.

[0119] As also illustrated in FIG. 8, if more than two nodes 80 areordered to be switched “ON” simultaneously (for example, nodes 80(2),80(5), and 80(6) in FIG. 8), the interpolating function 88 switches “ON”a phantom node 80(2, 5, 6) at the geometric center of the three or moreelectrode nodes 80.

[0120]FIG. 24 shows an image of several nodes 80(1) to 80(4),corresponding to the arrangement of electrodes 22(1) to 22(4) along asingle spline 20 shown in FIG. 23. In the FIG. 23 embodiment (aspreviously described), the electrodes 22(1) to 22(4) serve as thetransmitting electrodes, and they are energized simultaneously. As shownin FIG. 23 (and as previously described), the roving element 12 carriesmultiple sensing electrodes 30(1), 30(2), and 30(3). The generation ofmultiple, simultaneous proximity-indicating outputs (as previouslydescribed) orders node 80(4) to be switched “ON” due to its closecondition to both roving electrode 30(1) and 30(2); node 80(3) to beswitched “ON” due to its close condition to both roving electrodes 30(2)and 30(3); and node 80(2) switched “ON” due to its close condition toroving electrode 30(3). The interpolating function 88 switches “ON”phantom nodes (3,4) and (2,3), mid-way between the nodes (2) and (3) andmidway between the nodes (3) and (4). As FIG. 24 shows, switched “ON”node (4) and the switched “ON” phantom nodes (3,4) and (2,3)collectively create a pattern that matches both the actual position andgeneral orientation of the roving electrodes 30(1) to 30(3) relative tothe electrodes 22(1) to 22(4), as shown in FIG. 23.

[0121] The display of the proximity-indicating outputs P_((A,B))continuously tracks movement of the roving electrode 30 and electrodes30(1), 30(2) and 30(3) relative to the electrodes (A,B) on the structure14.

[0122] E. Electrically Identifying Structures

[0123] The system 10 an be used in association with a family of basketstructures 14. Basket structures 14 within the family are characterizedby different physical properties, such as the size of the structure 14;the shape of the structure 14; the radial symmetry or asymmetry of thestructure 14; the axial symmetry or asymmetry of the structure 14; thenumber of spline elements 20; the total number of electrodes 22 carriedby the structure 14; the number of electrodes 22 carried per splineelement 20; the distance between electrodes 22 on each spline element20; the distribution or density pattern of electrodes 22 on thestructure 14; or combinations thereof.

[0124] As FIG. 6 shows, the system 10 includes identification codes 94to identify individual basket structures 14 within the family of basketstructures. Each identification code 94 uniquely identifies a particularbasket structure 14 in terms of its physical property or properties.

[0125] As FIG. 6 shows, the code 94 is carried by a coded component96,which is attached in association with each basket structure 14. Inthe illustrated embodiment, the coded component 96 is located within ahandle 98 attached at the proximal end of the catheter tube 45 thatcarries the basket structure 14. However, the component 96 could belocated elsewhere on the catheter tube 45 or structure 14. The code 94can also be manually inputted by the physician using the keyboard 66.

[0126] The coded component 96 can be variously constructed. It can, forexample, take the form of an integrated circuit, which expresses indigital form the code 94 for input in ROM chips, EPROM chips, RAM chips,resistors, capacitors, programmed logic devices (PLD's), or diodes.Examples of catheter identification techniques of this type are shown inJackson et al. U.S. Pat. 5,38 3,874, which is incorporated herein byreference.

[0127] Alternatively, the coded component 96 can comprise separateelectrical elements, each one of which expresses an individualcharacteristic. For example, the component 96 can comprise severalresistors having different resistance values. The different independentresistance values express the digits of the code 94.

[0128] The coded component 96 is electrically coupled to an externalinterpreter 100 when the basket structure 14 is plugged into the centralprocessing unit 28 for use. The interpreter 100 inputs the code 94 andelectronically compares the input code 94 to, for example, apreestablished master table 102 of codes contained in memory. The mastertable 102 lists, for each code 94, the physical characteristics of thestructure 14. The interpreter 100 generates a identification output 104based upon the table 102. The graphical control program 82 retains alibrary of idealized graphical images that reflect the differentgeometries identified by the output 104. Based upon the identificationoutput 104 received from the central processing unit 28, the controlprogram 82 generates the particular idealized graphical image 74 thatcorresponds to the geometry of the particular basket structure 14 inuse.

[0129] F. Use With Cardiac Diagnosis and Treatment Systems

[0130] In a preferred embodiment (see FIG. 9), the system 10 forms apart of a modular system 106, which is used to diagnose and treatabnormal cardiac conditions. FIG. 9 shows a representative embodiment ofthe modular system 106 of which the system 106 forms a part. Additionaldetails of the modular system 106 not material to the invention can befound in copending U.S. patent application Ser. No. 08/813,62 4,entitled “Interface Unit for Use with Multiple Electrode Catheters,”filed Mar. 7, 1997.

[0131] In FIG. 9, the basket structure 14 and operative element 12 areshown deployed and ready for use within a selected region inside a humanheart H. FIG. 9 generally shows the basket structure 14 and operativeelement 12 deployed in the right ventricle RV of the heart H. Of course,the basket structure 14 and element 12 an be deployed in other regionsof the heart, too. It should also be noted that the heart shown in theFIG. 9 is not anatomically accurate. FIG. 1 shows the heart indiagrammatic form to demonstrate the features of the invention.

[0132] In FIG. 9, the basket structure 14 and element 12 have each beenseparately introduced into the selected heart region through a vein orartery (typically the femoral vein or artery) through suitablepercutaneous access. Alternatively, the basket structure 14 andoperative element 12 an be assembled in an integrated structure forsimultaneous introduction and deployment in the heart region.

[0133] Further details of the deployment and structures of the basketstructure 14 and element 12 are set forth in pending U.S. patentapplication Ser. No. 08/033,641, filed Mar. 16, 1993, entitled “Systemsand Methods Using Guide Sheaths for Introducing, Deploying, andStabilizing Cardiac Mapping and Ablation Probes.”

[0134] The electrodes (A,B) carried by the basket structure 14 areelectrically coupled to a signal processing system 108. The electrodes(A,B) sense electrical activity in heart tissue. The sensed activity isprocessed by the processing system 108 to assist the physician inidentifying the site or sites within the heart appropriate for ablation.This process, called mapping, can be accomplished in various way,according to the choice of the physician.

[0135] For example, the physician can condition the processing system108 to take multiple, sequential measurements of the transmission ofelectrical current by heart tissue to obtain tissue resistivitymeasurements. The processing of tissue resistivity signals to identifyappropriate ablation sites is disclosed in co-pending U.S. patentapplication Ser. No. 08/197,236, filed Jan. 28, 1994, and entitled“Systems and Methods for Matching Electrical Characteristics andPropagation Velocities in Cardiac Tissue to Locate Potential AblationSites.”

[0136] Alternatively, or in conjunction with tissue resistivitymeasurements, the physician can condition the processing system 108 toacquire and process electrograms in a conventional fashion.

[0137] The processing system 108 processes the electrogram informationto map the conduction of electrical impulses in the myocardium.

[0138] The identification code 94 previously described can also identifya functional property of the electrodes (A,B) on the basket structure 14in terms of a diagnostic capability, such as mapping, or derivation ofan electrical characteristic, or pacing. The processing system 108 caninclude functional algorithms 109, which set operating parameters basedupon the code 94. For example, the code 94 can provide input to tissuemapping algorithms to enable early activation detection, orfractionation mapping, or pace mapping, or entrainment pacing. The code94 can also provide input to electrical characteristic derivationalgorithms, or provide interpolation for evaluating electrograms betweenelectrodes, or extrapolate sensed electrical activities to locatepotential ablation sites.

[0139] The electrode 30 on the operative element 12 also serves as anablation electrode. Of course, other configurations employing multipleablation electrodes are possible, as described in pending U.S. patentapplication Ser. No. 08/28 7,310, filed Aug. 8, 1994, entitled “Systemsand Methods for Ablating Heart Tissue Using Multiple ElectrodeElements.”

[0140] A catheter tube 44 which carries the operative element 12includes a steering mechanism 110 contained within a proximal handle 112see FIG. 2B also). As FIG. 2B shows, the steering mechanism 110electively bends or flexes the catheter tube 44 to bring the operativeelement 12 nd ablation electrode 30 into conforming, intimate contactagainst the endocardial tissue. Details of the steering mechanism areshown in U.S. Pat. No. 5,254,088, which is incorporated herein byreference.

[0141] The ablation electrode 30 is electrically coupled to a generator114 of ablation energy. The type of energy used for ablation can vary.Typically, the generator 114 supplies electromagnetic radio frequencyenergy, which the electrode 30 emits into tissue.

[0142] The operative element 12 an also carry a code 120, in the samemanner as the code 94 is carried by the basket structure 14. The code120 identifies the physical characteristics of the element 12, such asits diagnostic function or its therapeutic functions. The code 120, canalso identify the physical characteristics of the ablation electrode 30,such as its size and the presence or absence of temperature sensingcapabilities. Based upon the code 120, the central processing unit 28can condition the ablation energy supply functions of the generator 114,such as by setting maximum or minimum power, and enabling specializedablation control algorithms, e.g., by tissue temperature sensing.

[0143] The physician places the ablation electrode 30 in contact withheart tissue at the site identified by the basket structure 14 forablation. The ablation electrode 30 emits ablating energy to heat andthermally destroy the contacted tissue.

[0144] The system 10 is electrically coupled to the basket structure 14and the operative element 12 as already described. The system 10collects and processes information to generate proximity-indicatingoutputs P_((A,B)) regarding the proximity of the ablation electrode 30relative to the electrodes (A,B) on the structure 14. The display of theproximity-indicating outputs P_((A,B)) as previously described, witheron the hardware grid 58 or the GUI 62, continuously tracks movement ofthe ablation electrode 30 relative to the electrodes (A,B) on thestructure 14. The display of the proximity-indicating outputs P_((A,B))thereby aids the physician in guiding the ablation electrode 30 intocontact with tissue at the site identified for ablation.

[0145] G. Patient Data Base

[0146] In a preferred embodiment (see FIGS. 9, 10A, and 10B), thegraphical control program 82 includes a MARKERS function 116. The MARKERfunction 116 enables the physician to alter and enhance the displayedmodel image 74 of the basket structure 14.

[0147] The MARKERS function 116 enables the operator to annotate theimage by adding an identifier or marker to selected locations of theimage 74. As FIG. 10A shows, the MARKERS function 116 is activated byclicking the ADD MARKER button 118 hat appears on the screen 68 afterthe general “MARKERS” button 120 is clicked on the Toolbar 150. Pressingthe right mouse button on an electrode (A,B) causes a marker 122 toappear on the screen. With the right mouse button depressed, thephysician can “drag” the marker 122 to the desired location. When theright mouse button is released, the marker 122 is “dropped” into thedesired marker location.

[0148] The MARKERS function 116 also enables the physician to add customannotations in the form of notes or comments to each marker 122. As FIG.10A shows, a COMMENT window 124 appears as soon as the marker 122 is“dropped” at the selected site. A time stamp is preferably automaticallyincluded in the comment window 124. The operator can enter the desiredcomment into the comment window 124 using the computer keyboard.

[0149] As FIG. 10B best shows, markers 122 and comments 124, can beplaced near electrodes on either the foreground or background of theimage 74, e.g., to mark selected locations that are significant or ofinterest, such as mapping sites, ablation sites, etc. The physician isthereby better able to remain coordinated and oriented with thedisplayed image and, therefore, better able to interpret data recoveredby the basket structure 14.

[0150] By clicking a pop up SAVE button 126 (or alternatively, clickingthe Save View button 152 on the Toolbar 150) at desired times, theentire graphical display, including model image 74, markers 122, andassociated comment windows 124 can be saved as a data file record forstorage, retrieval, or manipulation. The physician is thereby able tocreate during a given diagnostic or therapeutic procedure apatient-specific data base 128, stored in on board memory, which recordsthe diagnostic or therapeutic events of the procedure. Further detailsabout the patient data base 128 will be described later.

[0151] In the illustrated embodiment (see FIG. 9), a control line 130couples the generator 114 to the graphic control software 82.Transmission of ablation energy by the generator 114 generates an outputsignal in the control line 130. The output signal commands the controlprogram 82 to automatically save the entire graphical display as itexists at the instant ablation occurs. The physician is thereby able torecord each ablation event in the context of a graphical image forinclusion in the data base 128 specific to the patient.

[0152] The output signal commands identification of the location of theablation electrode, generates a time stamped marker 122, and generate anablation-indicating annotation, e.g., a comment window 124 or marker122, identifying the position of the electrode at the instant ablationoccurs.

[0153] To establish and maintain records in the patient data base 128,the graphical control program 82 includes a PATIENT DATA function 132.As FIG. 11 shows, at the time that the control program 82 generates theOperational Screen Toolbar 150 (previously described), the controlprogram 82 also opens a Patient Data Window 134. The Patient Data Window134 allows the physician to enter data about the particular patient andthereby make patient specific subsequent information recorded and savedin the data base 128.

[0154] To create a patient-specific record in the data base 128, thephysician enters in the Patient field 136 of the Window 134 the name ofthe patient and clicks the New Study button 138. The control program 82enters a default file name in a Study Name field 140, with associatedtime marker 142. The physician can enter in the Text field 144additional information or comments regarding the patient, such as thepatient's ID number, age, etc, which the physician wants to save as partof the patient record. The physician can also enter diagnosticinformation, e.g., heart tissue pacing data; or therapeutic information,e.g., heart tissue ablation data; or identify the attending physician orstaff personnel. The physician can also select in the Device field 146the type of structure 14 that will be deployed in the patient. Thephysician can then click the open Study button 148 to begin the newstudy.

[0155] When beginning a new study, the control program 82 gives thephysician the option of starting the new study with new image views inthe left and right panels 76 and 78 (by clicking the Reset button 160 onthe Toolbar 150, as shown in FIG. 7). The Toolbar 150, previouslydescribed, allows the physician to customize the left and right panelimages 74 for the new study, in the manner previously described inconnection with FIG. 7.

[0156] Alternatively, the control program 82 gives the physician theoption of using the same image views set in an immediately precedingstudy. This option allows the physician to quickly switch amongdifferent diagnostic or therapeutic protocols (each constituting a“study”) on the same patient using the same structure 14 in the sameheart chamber.

[0157] During a given study, the physician can implement the MARKERSfunction 116 to set up markers 122 and comment windows 124 inassociation with the selected image views, as FIGS. 10A and 10B show. Inthe comment windows 124, the physician can include further informationidentifying the procedure, diagnostic information, therapeuticinformation, or otherwise annotate the image. By clicking the SAVE viewbutton 126 on the Toolbar 150 at desired times, the entire graphicaldisplay, including model image 74, markers 122, and associated commentwindows 124 are saved as a data file uniquely associated for theparticular study and particular patient for storage, retrieval, ormanipulation. The control program 82 gives the physician the option ofprotecting the data by use of a password, to restrict access to all orsome of the data base records.

[0158] As FIG. 9 shows, an output device, such as a printer 164 orgraphics display terminal 166, allows patient record information to berecalled or down loaded for off-line analysis or compilation. Thepatient record will contain the entire graphical image 74 (includingshape characteristics or orientations added by the physician), markers122, and associated comment windows 124 in existence at the time therecord was saved. As FIG. 11 shows, the patient study Window 134 canwith time markers 142 provide information documenting the storage,retrieval, or manipulation of the data base record, such as the date onwhich data in the record is entered or updated, or the date on whichdata was retrieved or otherwise manipulated.

[0159] As FIG. 9 also shows, a communications port 168 allows patientrecord information to be transmitted to a central data storage station170. A network of local or remote systems 106, 106(A), 106(B), and106(C), each having all or some of the features described for module106, can be linked to the central data storage station 170, by anInternet-type network, or by an intranet-type network. The network ofwork station modules 106, 106(A), 106(B), and 106(C), all linked to thecentral data storage station 170, allows patient-specific data baserecords for many patients at one or more treatment facilities to bemaintained at a single location for storage, retrieval, or manipulation.

[0160] To exit the control program 82, the physician clicks thePatient/Quit button 162 on the Toolbar 150 (see FIG. 7).

[0161] II. Proximity Sensing Using Other Structures

[0162] A. Elongated Structures

[0163]FIG. 12 shows another embodiment of a position sensing system 168,which locates the position of an operative element 170 along a locatingprobe 172. In FIG. 12 the locating probe 172 takes the form of anelongated electrode array 174.

[0164] The operative element 170 is constructed in the same way as theelement 12 previously described and shown in FIG. 2B. As FIG. 13 shows,the element 170 is carried at the distal end of a catheter tube 176.However, like the element 12, the element 170 need not be necessarilycatheter-based.

[0165] As earlier described, the operative element 170 can be used foreither therapeutic purposes, or diagnostic purposes, or both. In theillustrated embodiment, the operative element 170 includes an electrode178, which can be conditioned to sense a physiological characteristic inmyocardial tissue. The electrode 178 can also be conditioned to transmitelectrical energy to stimulate (i.e., pace) myocardial tissue, as wellas transmit radio frequency energy to ablate myocardial tissue.

[0166] As shown in FIG. 12 the elongated array of electrodes 174 arealso carried at the distal end of a catheter tube 180 in the same waythat the structure 14 is carried by a catheter tube 45 in FIG. 2A. Inthe illustrated embodiment, the electrodes 174 take the form ofconventional rings 175 of electrically conductive material (e.g., copperalloy, platinum, or stainless steel), arranged in a spaced apart,segmented relationship about a sleeve 182 of electrically insulatingmaterial. Alternatively, the electrodes 174 can be coated upon thesleeve 182 using conventional coating techniques or an ion beam assisteddeposition (IBAD) process, or comprise spaced apart lengths of wound,spiral coils made of electrically conducting material.

[0167] In the illustrated embodiment, the distal regions of bothcatheter tubes 176 and 180 can be flexed using an on board steeringmechanism (not shown). The feature has been previously described inassociation with the first described embodiment and is shown in FIGS. 2Aand 2B.

[0168]FIG. 13 shows the operative element 170 and array of electrodes174 deployed in the annulus region 184 of a human heart H. FIG. 13 showsthe deployment diagrammatically and not with anatomic precision.

[0169] The annulus region 184 lays at the intersection of the atrialstructure 186 and the ventricular structure 186 of the heart. Theannulus region 184 is a site where the electrophysiological source ofmany arrhythmias can be mapped and successfully eliminated by ablation.

[0170] In FIG. 13, the operative element 170 and its electrode 178 areshown deployed inside an atrium 194 near the annulus region 184. Thephysician is able to selectively move the element 170 along theendocardial surface 196 inside the atrium at or near the annulus region184.

[0171] As shown in FIG. 13, the elongated array of electrodes 174 isdeployed outside the atrium 194, within an adjacent region of the greatcardiac vein 190. The great cardiac vein 190 is a fixed anatomicstructure, which extends close to the epicardium 192 along the annulusregion 184. The great cardiac vein 190 thereby serves as an anatomicmarker to aid the physician in situating the locating array ofelectrodes 174 in the annulus region 184.

[0172] As FIG. 12 shows, and functioning in the same manner aspreviously described with reference to FIG. 1, the central processingunit 28 conditions the oscillator 26 to transmit an electrical ACwaveform through the electrode 178 carried by the operative element 170.The indifferent electrode 32 comprises the voltage return, coupled to anelectrical reference, which, in the illustrated embodiment, is isolatedor patient ground 34. The voltage field that is created varies indetected amplitude at each electrode ring 175 according to its distancefrom the electrode 178 carried by the operative element 170. Aproximity-indicating output 198 (designated P_((A))) is generated in themanner previously described for a given electrode ring 175 (where Aequals 1to the number of electrode rings 175 on the array 174), when theprescribed “close condition” between the given ring electrode 175 andthe electrode 178 exists.

[0173] Since the position and orientation of the great cardiac vein 190is known, a graphic display 204 can generate an idealized graphicalimage 200 (see FIG. 14) for the electrode array 174, in which nodes 202mark the ring electrodes 175. The display 204 thereby graphicallydepicts for the physician an idealized graphical image of the portion ofthe annulus region 184 where the electrode array 174 is deployed.

[0174] Using the ring electrodes 174, the physician can pace and senseelectrical events in myocardial tissue along the annulus region 184. Intandem, the physician can also pace and sense using the electrode 178 onthe operative element 170. Pacing and sensing both inside and outsidethe atrium 194 permit the detection of differences betweenelectrophysiological activities near the epicardial surface (detected bythe ring electrodes 175) and near the endocardial surface (detected bythe electrode 178). This differential detection technique providesadvanced diagnostic capabilities.

[0175] Generation of the proximity-indicated output 198 (as previouslydescribed with reference to the basket structure 14) switches “ON” thenode 202 when the prescribed “close condition” to the roving electrode178 exits. The display 204 thereby tracks the movement of the rovingelectrode 178 along the annulus region 184 as mapping and diagnosticfunctions proceed.

[0176] Once mapping identifies a candidate ablation site, the display204 aids the physician in moving the electrode 178 to the site for thepurpose of transmitting ablation energy.

[0177] B. Loop Structures

[0178]FIG. 15 shows still another embodiment of a position sensingsystem 268 to locate the position of the same or equivalent operativeelement 170 and associated electrode 178 shown and described inconnection with the FIG. 13 embodiment. In this embodiment, the locatingprobe comprises a multiple electrode loop structure 274.

[0179] The loop structure 274 can be constructed in various ways. In theillustrated embodiment (see FIGS. 16 and 17), the structure 274 isformed from a core spline leg 246 covered with an electricallyinsulating sleeve 248. Multiple electrode elements 228 are secured onthe sleeve 248.

[0180] In the illustrated embodiment, the electrodes 228 take the formof conventional rings 275 of electrically conductive material (e.g.,copper alloy, platinum, or stainless steel), arranged in a spaced apart,segmented relationship about the sleeve 248. As previously described inconnection with the electrode array 174, the electrodes 174 can, in analternative construction, be coated upon the sleeve 248, or comprisespaced apart lengths of wound, spiral coils made of electricallyconducting material.

[0181] As demonstrated in FIG. 17, the ring electrodes 228 can bearranged in a prearranged pattern. In FIG. 17, the pattern comprisespaired groups of eight electrodes 228, separated by enlarged spacerrings 229. The pattern assists the physician to orient the structure 274when viewing it fluoroscopically.

[0182] The number of electrodes 228 can vary. Typically, between 10 and24 electrodes 228 are used.

[0183] The structure 274 is carried at the distal end of a catheter tube212. A sheath 302 is also carried by the catheter tube 212 As FIGS. 16and 17 show, the distal section 304 of the sheath 302 is joined to thedistal end 308 of the structure 274 by a short length of wire 306, e.g.,by adhesive or thermal bonding.

[0184] The catheter tube 212 slidable within the sheath 302 to deploythe structure 274. Pushing the catheter tube 212 n the forward directionthrough the sheath 302 (as shown by arrow 310 in FIG. 17), moves thestructure 274 outward from the end of the sheath 302. The wire 306 formsa flexible joint 344, pulling the distal end 308 of the structure 274toward the sheath 302. The structure 274 thereby is bent into a loop, asFIG. 17 shows. The physician can alter the diameter of the loopstructure 274 from large to small, by incrementally moving the cathetertube 312 in the forward direction (arrow 310 in FIG. 17) and rearwarddirection (arrow 316 in FIG. 17) through the sheath 302. Moving thestructure 274 fully in the rearward direction (arrow 316) returns thestructure 274 into a low profile, generally straightened configurationwithin the sheath 302 (as FIG. 16 shows), well suited for introductioninto the intended body region.

[0185]FIG. 18 shows the operative element 170 and structure 274 deployedin the annulus region 180 of a human heart H. Like FIG. 13, FIG. 18shows the deployment diagrammatically and is not intended to beanatomically accurate.

[0186] In FIG. 18, the loop structure 274 is deployed within an atrium194 of the heart H. Due to its geometry, the loop structure 274 tends toseek the largest diameter in the atrium 194 and occupy it. The region oflargest diameter in an atrium is typically located above and close tothe annulus region 184. The loop structure 274 thereby serves toreliably situate itself close to the annulus region 184.

[0187] In FIG. 18 the operative element 170 and its electrode 178 aredeployed in the space S immediately below (i.e., toward the ventricle188) of the loop structure 274, which is nearer to the annulus region184 than the loop structure 274. The physician is able to selectivelymove the element 170 along the endocardial surface within this space Snear the annulus region 184.

[0188] As FIG. 15 shows, and functioning in the same manner aspreviously described, the central processing unit 28 conditions theoscillator 26 to transmit an electrical AC waveform through theelectrode 178 carried by the operative element 170. The indifferentelectrode 32 comprises the voltage return, coupled to an electricalreference, which, in the illustrated embodiment, is isolated or patientground 34. The voltage field that is established varies in detectedamplitude at each electrode ring 228 on the loop structure 274 accordingto its distance from the electrode 178 carried by the operative element170. A proximity-indicating output 198 (designated P_((A))) is generatedfor a given electrode ring 228 (where A equals 1 to the number ofelectrode rings 228 on the loop structure 274), when the prescribed“close condition” between the given ring electrode 228 and the electrode178 exists.

[0189] As previously described in the context of other structures, agraphic display 250 can generate an idealized graphical image 252 (seeFIG. 19) for the loop electrode array 274, in which nodes 254 mark thering electrodes 228. A fluoroscope used in association with the display250 allows the physician to visualize the actual radius of curvature andorientation of the loop 274 in the atrium. The physician compares thefluoroscopic image and uses the Toolbar 150 (previously described) tomanipulate the graphic image 252 to more closely match the view of thefluoroscopic display. The physician can then use the Toolbar 150 toswitch views of the graphic image 252 electronically, withoutmanipulating the fluoroscopic display, as previously described.

[0190] Using the ring electrodes 228 on the loop structure 274, thephysician can pace and sense electrical events in myocardial tissuealong the annulus region 184.

[0191] Generation of the proximity-indicated output 198 switches “ON”the node 254(*) when the prescribed “close condition” to the rovingelectrode 178 exits. The display 250 thereby tracks the movement of theroving electrode 178 along the annulus region 184 as mapping anddiagnostic functions proceed.

[0192] Once mapping identifies a candidate ablation site, the display250 aids the physician in moving the electrode 178 to the site for thepurpose of transmitting ablation energy.

[0193] C. Dual Electrode Arrays

[0194]FIG. 27 shows another embodiment of a position sensing system 400,which locates the position of the same or equivalent operative element170 and associated electrode 178 shown and described in connection withthe preceding embodiments (FIGS. 12 and 15). In this embodiment (seealso FIG. 25), the locating probe comprises a three-dimensionalstructure 402 carrying dual outer and inner arrays of electrodes 404 and406.

[0195] As best shown in FIG. 25, the outer electrode array 404 comprisesan outer structure formed by spaced apart splines elements 408constrained between a base 418 and a hub 416, in the same manner as thebasket structure 14 shown in FIG. 1. Spline elements 408 are carried atthe distal end of a catheter tube 412 in the same way that the structure14 is carried by a catheter tube 45 in FIG. 2A. In FIG. 25, four splineelements 408 are shown for the purpose of illustration.

[0196] As in the basket structure 14, each spline element 408 carries anumber of electrodes 410. In FIG. 25, each spline element 408 carrieseight electrodes 410, for a total of thirty-two electrodes 410, in theouter electrode array 404. Of course, the outer electrode array 404 cancomprise a greater or lesser number of spline elements 408 and/orelectrodes 410 The hub 416 can also serve as an electrode on the outerarray 404.

[0197] The inner electrode array 406 shown in FIG. 25 comprises an innerstructure 414, formed of electrically insulating material, which issupported by and within the outer electrode array 404. As shown in FIG.25, the inner structure 414 is retained by a center support wire 420between the hub 416 and base 418.

[0198] In FIG. 25, the inner structure 414 is shown to be a cylindricaltube. However, the inner structure 414 can take other shapes and beconstructed differently.

[0199] For example, as shown in FIG. 26, the inner structure 414 cancomprise an expandable balloon 422. The proximal end of the balloon 422extends through the base 418 into the interior of the outer electrodearray 404. A support wire 424 extends from the distal end of the balloon422 and is attached to the hub 416. A lumen 423 in the associatedcatheter tube 412 carries an inflation fluid into the balloon 422, toexpand it at time of use. In FIG. 26, when inflated, the balloon 422 hasa preformed elliptical shape.

[0200] Regardless of its shape or construction, the inner structure 414carries an array of electrodes 426, position in a spaced-apart patternon the structure 414. The electrodes 426 can comprise metallic strips ofelectrically conductive material (e.g., copper alloy, platinum, orstainless steel), attached in the spaced apart pattern on the innerstructure 414. Alternatively, the electrodes 426 can be coated on theinner structure 414, using conventional coating techniques or an ionbeam assisted deposition (IBAD) process. Preferably, the electrodes 410on the outer structure 404 and the electrodes 426 on the inner structure406 are made of substantially equivalent materials.

[0201] The number of electrodes 426 carried by the inner structure 414can vary. Preferably, the number of electrodes 426 on the innerstructure 414 should at least equal the number of electrodes 410 n theouter structure 404.

[0202] As FIG. 27 shows, the central processing unit 28 conditions theoscillator 26 to transmit an electrical AC waveform through theelectrode 178 carried by the operative element 170. The indifferentelectrode 32 comprises the voltage return, coupled to an electricalreference, which, in the illustrated embodiment, is isolated or patientground 34. The voltage field that is established varies in detectedamplitude at each electrode 410 or 426 according to its distance fromthe electrode 178 carried by the operative element 170. The switch 38serves to couple the data acquisition element 36 to selected electrodes410 on the outer array 404 or selected electrodes 426 on the inner array406, or both.

[0203] A proximity-indicating output 198 (designated P_((A))) isgenerated in the manner previously described for a given electrode 410or 426, when the prescribed “close condition” between the givenelectrode 410 or 426 and the electrode 178 exists.

[0204] The electrodes 410 on outer electrode array 404 provideinformation for localizing the roving operative element 170 when itresides close to the tissue walls of the interior body region, e.g.,near the endocardial wall, when the structure 402 is deployed in a heartchamber. The electrodes 426 on the inner electrode array 406 provideinformation for localizing the roving operative element 170 when itresides close to the central region of the interior body region, e.g.,inside a heart chamber away from the endocardial wall. Voltage amplitudesensing can be accomplished in sequence by groups of electrodes 410 onthe outer array 404, groups of electrodes 426 on the inner array 406, orby groups of electrodes distributed on both the inner and outer arrays404 and 406.

[0205] As FIG. 28 shows, a graphic display 428 can generate an idealizedgraphical image 430 for the dual electrode array structure 402, in whichnodes 432 mark the electrodes 410 and 426.

[0206] Using the electrodes 410 on the outer array 404, the physiciancan pace and sense electrical events in myocardial tissue. Generation ofthe proximity-indicated output 198 (as previously described withreference to the basket structure 14) switches “ON” the node 434 whenthe prescribed “close condition” to the roving electrode 178 exits.Coupled to the dual array sensing structure 402, the display 428 tracksthe movement of the roving electrode 178 both near to and far fromtissue as diagnostic and therapeutic functions proceed.

[0207] Once mapping identifies a candidate ablation site, the display428 aids the physician in moving the electrode 178 to the site for thepurpose of transmitting ablation energy.

[0208] The dual array structure 402 can be used in association with theelongated electrode structure 174 or the loop structure 274, previouslydescribed. Use of the dual array structure 402 can provide improvednavigational accuracy, particularly in interior body regions, away fromthe tissue wall.

[0209] All the previously described features of the GUI 62 can beemployed in association with the graphical images 202, 250, or 430. Theinterpolation function 88 can be used to interpolate multipleproximity-indicated output 198 in the manner shown in FIGS. 8 and 24.Identification codes 94 can be used in the manners shown in FIG. 9 touniquely identify the particular geometries and physical characteristicsof the elongated structure 174, the loop structure 274, the multiplearray structure 402, or an other structure deployed. The codes 94 can beemployed to create the idealized image 202 or 250 or 430, which can befurther manipulated by input from the physician, in the same manner aspreviously described. Markers 122 and comment windows 124 can begenerated in the image 202 or 250 or 430, in the same manner aspreviously described in connection with FIGS. 10A and 10B. The graphicalimage 202 or 250 or 430, with associated markers 122 and comment windows124, can be periodically saved during mapping, and again saved at theinstant of ablation, and retained in the patient-specific data base 128,as previously described.

[0210] Use of the elongated electrode structure 174, the loop structure274, and the dual array structure 402 has been described, during whichthe electrical field is transmitted by the electrode 178 on theoperative element 170 to the indifferent electrode 32, and theelectrical field is sensed by electrodes carried on the structure 174,274, or 402. However, it should be appreciated that, as in theembodiment shown in FIGS. 20 to 24, the electrical field can betransmitted by one or more electrodes on the structure 174, or 274, or402 (simultaneously or in sequence) to the indifferent electrode 32, forsensing by the electrode 178 on the operative element 170. The operativeelement can also carry multiple sensing electrodes 178 to provideorientation information as well as proximity information, as previouslydescribed in connection with FIGS. 22 and 23.

[0211] Furthermore, with respect to the dual array structure 402, theelectrical field can be transmitted to the indifferent electrode 32 bygroups of electrodes on the outer array 404, or groups of electrodes onthe inner array 406, or groups of electrodes distributed on both theouter and inner arrays 404 and 406. In this arrangement, the rovingelectrode 178 (or electrodes, if present) on the operative element 170can be used to sense the voltage amplitude.

[0212] The foregoing GUI and implementing control programs can beimplemented using the MS WINDOWS™ application and the standard controlsprovided by the WINDOWS™ Development Kit, along with conventionalgraphics software disclosed in public literature.

[0213] Various features of the invention are set forth in the followingclaims.

We claim:
 1. A system to record use of a structure deployed in operativeassociation with heart tissue in a patient comprising an imagecontroller to generate an image of the structure while in use in thepatient, an input to receive data including information identifying thepatient, and an output to process the image in association with the dataas a patient-specific, data base record for storage, retrieval, ormanipulation.
 2. A system comprising a structure, which, in use, isdeployed in operative association with heart tissue in a patient, thestructure carrying an operative element, a device coupled to theoperative element to condition the operative element to perform adiagnostic or therapeutic procedure involving the heart tissue whiledeployed in the patient, an image controller to generate an image of thestructure at least partially while the operative element performs theprocedure, an input to receive data including information identifyingthe patient, and an output to process the image in association with thedata as a patient-specific, data base record for storage, retrieval, ormanipulation.
 3. A system according to claim 2 wherein the electrodestructure comprises an elongated body.
 4. A system according to claim 2wherein the electrode structure comprises a loop.
 5. A system accordingto claim 2 wherein the structure comprises a three-dimensional basket.6. A system according to claim 2 wherein the structure comprises anouter electrode element and an inner array of electrode element locatedwithin the outer electrode element.
 7. A system according to claim 1 or2 wherein the image controller is coupled to the input to display thedata in association with the image.
 8. A system according to claim 1 or2 wherein the data further includes information identifying theprocedure.
 9. A system according to claim 1 or 2 wherein the dataincludes diagnostic information.
 10. A system according to claim 9wherein the diagnostic information includes heart tissue pacing data.11. A system according to claim 1 or 2 wherein the data includestherapeutic information.
 12. A system according to claim 11 wherein thetherapeutic information includes heart tissue ablation data.
 13. Asystem according to claim 1 or 2 wherein the data includes time stampedinformation.
 14. A system according to claim 1 or 2 wherein the dataincludes processing information documenting the storage, retrieval, ormanipulation of the data.
 15. A system according to claim 14 wherein theprocessing information includes a date on which data was entered intothe data base record.
 16. A system according to claim 14 wherein theprocessing information includes a date on which data was retrieved fromthe data base record.
 17. A system according to claim 1 or 2 wherein thedata includes information identifying a person other than the patient.18. A system according to claim 1 or 2 wherein the outputpassword-protects the data base record.
 19. A system according to claim1 or 2 wherein the image controller includes an adjustment function toalter appearance of the image in response to operator input before orafter processing by the output.
 20. A system according to claim 19wherein the adjustment function alters orientation of the image beforeor after processing by the output.
 21. A system according to claim 19wherein the adjustment function alters shape of the image before orafter processing by the output.
 22. A system according to claim 19wherein the adjustment function alters view aspects of image before orafter processing by the output.
 23. A system according to claim 1 or 2wherein the image controller includes a comment function to insertannotations in the image in response to operator input before or afterprocessing by the output.
 24. A system according to claim 1 or 2 whereinthe image controller includes a marker function to mark one or moreregions of the image in response to operator input before or afterprocessing by the output.
 25. A system according to claim 1 or 2 whereinthe image generated by the image controller comprises an idealizedgraphical image.
 26. A system according to claim 1 or 2 wherein theimage controller generates a proximity-indicating output showing theproximity of a roving element, deployed in the patient, to thestructure.
 27. A system according to claim 24 wherein the outputprocesses the proximity-indicating output with the image as part of thepatient-specific, data base record.
 28. A system according to claim 24wherein the image controller includes an input for establishing aproximity threshold for the proximity-indicating output.
 29. A systemaccording to claim 28 wherein the output processes the proximitythreshold with the image as part of the patient-specific, data baserecord.
 30. A system according to claim 1 or 2 wherein the imagecontroller is adapted to be coupled to a source of ablation energy togenerate an ablation-indicating annotation when ablation energy isapplied to the heart tissue of the patient.
 31. A system according toclaim 30 wherein the output processes the ablation-indicating annotationwith the image as part of the patient-specific, data base record.
 32. Asystem according to claim 30 wherein the image controller generates anablation-proximity output on the image showing a location where ablationenergy is applied.
 33. A system according to claim 30 wherein the outputprocesses the ablation-proximity output with the image as part of thepatient-specific, data base record.
 34. A system according to claim 1 or2 and further including a central station coupled to the output.
 35. Asystem according to claim 1 or 2 and further including a printer coupledto the output.
 36. A system according to claim 1 or 2 and furtherincluding a display device coupled to the output.
 37. A system accordingto claim 1 or 2 and further including a communications port coupled tothe output.
 38. A system according to claim 1 or 2 wherein the imagecontroller generates a graphical user interface that includes the image.39. A system for diagnosing or treating cardiac conditions of multiplepatients comprising a network of local work stations, each one adaptedto be coupled to an electrode structure, which, in use, is deployed inoperative. association with heart tissue of a patient, the device beingoperative to condition the electrode structure to perform a diagnosticor therapeutic procedure involving the heart tissue, each local workstation including an image controller to generate an image of thestructure at least partially while the operative element performs theprocedure, an input to receive data including information identifyingthe patient, and an output to process the image in association with thedata as a patient-specific, data base record for storage, retrieval, ormanipulation, and a central terminal coupled to the output of each workstation to receive the patient-specific data base records for all workstations for storage in a central patient data base.
 40. A systemaccording to claim 39 and further including a printer coupled to thecentral terminal.
 41. A system according to claim 39 and furtherincluding a display device coupled to the central terminal.
 42. A systemaccording to claim 39 and further including a communications portcoupled to the central terminal.
 43. A system according to claim 39wherein the image controller of at least one of the work stationsgenerates a graphical user interface that includes the image.
 44. Asystem according to claim 39 and further including a local memory unitcoupled to the output of at least one work station to store apatient-specific data base record generated by the at least one workstation.
 45. A system according to claim 39 wherein the output of atleast one work station is coupled to the central terminal using anInternet-type network.
 46. A system according to claim 39 wherein theoutput of at least one work station is coupled to the central terminalusing an intranet-type network.